Anecdotally, this week was not bad until Wednesday, has been very busy since (especially yesterday and this morning). But signs have been in place for phased closings all week, have not been used. I'll be surprised if MK doesn't at least go Phase 1 today and tomorrow.
From what I hear, even Universal hasn't felt the need to use switchbacks in Diagon.
A lot of it just how the calendar falls. Talking with northern friends, some kids got a March break rather than full week at Easter (although not true of all of them). Also, I imagine snow days cut short quite a few Spring Breaks, as schools try to make up days.
I don't see any Phased Closings threads here, so I'm going to guess that we made it through Easter and Spring Break with none. Guess were good until July 4th now!
Based on crowds at SoFla beaches, it appears we hit our peak about three weeks ago now and it's been steadily downhill since. I'd guess within two weeks all the snowbirds will be heading back to northern climes.